This study will test the hypothesis that women with masticatory muscle disorders (MMDs) have an underlying hypofunction of the HPA axis similar to that seen in fibromyalgia. These studies will provide an understanding of the pathophysiological basis of the puzzling relationship of MMD to seemingly disparate conditions such as fibromyalgia and depressive disorders, as well as the higher prevalence in women, leading to a more rational basis for diagnosis and treatment of MMD.